How do I get Lumia 1020 to recognize SIM?

The phone is a Developer Seeding and the IMEI is clean and unlocked. However, when I put my t-mobile micro SIM in from my lumia 925, it will not recognize the SIM. The phone shows no carrier, so one would assume I could just use my existing SIM. I spoke with T-Mobile and the tech said the SIM is not paired with the IMEI and that I would need to get a new SIM and have it programmed with my number and the phones IMEI...Is this correct?

Not really. T-Mobile gave you BS as expected. I would first check if the phone accepts any other SIM in a workable fashion. If it does then I would check the existing T-Mobile SIM on another device or get a new replacement SIM.

Hmm, inferring from what the T-Mobile tech said, is your Lumia 925 locked to T-Mobile? Is it possible that your SIM is locked to your Lumia 925 and hence can't be used in a different phone? The problem could be not with the L1020, but that the SIM is locked to that particular L925.

Check with T-Mobile for the specifics about your account. If your SIM is not locked to that phone, then getting a new SIM should not be difficult.

You could also try using a different SIM in your L1020 if you have access to some - just to see if nothing is wrong with your L1020.

Hmm, inferring from what the T-Mobile tech said, is your Lumia 925 locked to T-Mobile? Is it possible that your SIM is locked to your Lumia 925 and hence can't be used in a different phone? The problem could be not with the L1020, but that the SIM is locked to that particular L925.

GSM SIMs are not tied to a particular phone. In this case it's either the SIM or the SIM contacts on the phone's motherboard (hardware repair needed)